NERC Petition (without exhibits)

UNITED STATES OF AMERICA
BEFORE THE
FEDERAL ENERGY REGULATORY COMMISSION
North American Electric Reliability
Corporation

)
)

Docket No. __________

PETITION OF THE
NORTH AMERICAN ELECTRIC RELIABILITY CORPORATION
FOR APPROVAL OF PROPOSED RELIABILITY STANDARD PRC-005-3
(PROTECTION SYSTEM MAINTENANCE)
Gerald W. Cauley
President and Chief Executive Officer
North American Electric Reliability
Corporation
3353 Peachtree Road, N.E.
Suite 600, North Tower
Atlanta, GA 30326
(404) 446-2560
(404) 446-2595 – facsimile

Charles A. Berardesco
Senior Vice President and General Counsel
Holly A. Hawkins
Assistant General Counsel
William H. Edwards
Counsel
Brady A. Walker
Associate Counsel
North American Electric Reliability
Corporation
1325 G Street, N.W., Suite 600
Washington, D.C. 20005
(202) 400-3000
(202) 644-8099 – facsimile
[email protected]
[email protected]
[email protected]
[email protected]
Counsel for the North American Electric
Reliability Corporation

February 14, 2014

TABLE OF CONTENTS

I.

EXECUTIVE SUMMARY .................................................................................................... 2

II.

NOTICES AND COMMUNICATIONS ................................................................................ 3

III. BACKGROUND .................................................................................................................... 4
A.

Regulatory Framework ..................................................................................................... 4

B.

NERC Reliability Standards Development Procedure ..................................................... 5

C.

History of Project 2007-17.2 ............................................................................................ 6

IV. JUSTIFICATION FOR APPROVAL..................................................................................... 7
A.

Reclosing Relays .............................................................................................................. 9

B.

SAMS/SPCS Report......................................................................................................... 9

C.

Modifications in proposed Reliability Standard PRC-005-3 ......................................... 12
1.

Definitions .................................................................................................................. 12

2.

Applicability ............................................................................................................... 14

3.

Changes to Requirements in Reliability Standard PRC-005-2 ................................... 21

D.

E.

Implementation Plan ...................................................................................................... 22
1.

Retirement of Legacy Reliability Standards ............................................................... 23

2.

Compliance Timeframes for Each Requirement ........................................................ 24

3.

Newly Identified Automatic Reclosing Components ................................................. 24
Evidence Retention Periods ........................................................................................... 25

F. Enforceability of proposed Reliability Standard PRC-005-3 ............................................ 26
V.

CONCLUSION ..................................................................................................................... 27

Exhibit A

Proposed Reliability Standard PRC-005-3

Exhibit B

Implementation Plan for PRC-005-3

Exhibit C

Order No. 672 Criteria for PRC-005-3

Exhibit D

NERC SAMS-SPCS Joint Autoreclosing Report

Exhibit E

Supplementary Reference and FAQ Document

Exhibit F

Table of Issues and Directives

i

TABLE OF CONTENTS
Exhibit G

Analysis of Violation Risk Factors and Violation Security Levels

Exhibit H

Summary of Development History and Complete Record of Development

Exhibit I

Protection System Maintenance and Testing Standard Drafting Team Roster for
Project 2007-17.2

ii

UNITED STATES OF AMERICA
BEFORE THE
FEDERAL ENERGY REGULATORY COMMISSION
North American Electric Reliability
Corporation

)
)

Docket No. __________

PETITION OF THE
NORTH AMERICAN ELECTRIC RELIABILITY CORPORATION
FOR APPROVAL OF PROPOSED RELIABILITY STANDARD PRC-005-3
(PROTECTION SYSTEM MAINTENANCE)
Pursuant to Section 215(d)(1) of the Federal Power Act (“FPA”)1 and Section 39.52 of the
Federal Energy Regulatory Commission’s (“FERC” or “Commission”) regulations, the North
American Electric Reliability Corporation (“NERC”)3 hereby submits for Commission approval:


proposed Reliability Standard PRC-005-3 (Protection System Maintenance) (Exhibit A);



one new (Automatic Reclosing) and five revised definitions (Unresolved Maintenance
Issue, Segment, Component Type, Component, and Countable Event)4;



the implementation plan for proposed Reliability Standard PRC-005-3 (“Implementation
Plan”) (Exhibit B); and



the Violation Risk Factors (“VRFs”) and the revised Violation Severity Levels (“VSLs”)
for proposed PRC-005-3 (Exhibit A and Exhibit G).

1

16 U.S.C. § 824o (2012).
18 C.F.R. § 39.5 (2014).
3
The Commission certified NERC as the electric reliability organization (“ERO”) in accordance with
Section 215 of the FPA on July 20, 2006. N. Am. Elec. Reliability Corp., 116 FERC ¶ 61,062 (2006).
4
These terms were approved as PRC-005 specific definitions along with the approval of Reliability Standard
PRC-005-2. See Protection System Maintenance Reliability Standard, Order No. 793, 145 FERC ¶ 61,253 (2013).
The definitions can be found in the posted PRC-005-2 Reliability Standard. Once approved, the revised versions of
the definitions will located in the posted version of proposed PRC-005-3.
2

1

NERC requests that the Commission approve the proposed Reliability Standard and find that it is
just, reasonable, not unduly discriminatory or preferential, and in the public interest. 5 NERC
also requests approval of the retirement of Reliability Standard PRC-005-26 as detailed in the
Implementation Plan.
As required by Section 39.5(a)7 of the Commission’s regulations, this petition presents
the technical basis and purpose of proposed Reliability Standard PRC-005-3, a summary of the
development history (Exhibit H), and a demonstration that the proposed Reliability Standard
meets the criteria identified by the Commission in Order No. 6728 (Exhibit C). Proposed
Reliability Standard PRC-005-3 was approved by the NERC Board of Trustees on November 7,
2013.
I.

EXECUTIVE SUMMARY
In Order No. 758, the Commission directed NERC to include maintenance and testing of

reclosing relays that can affect the Reliable Operation of the Bulk-Power System in Reliability
Standard PRC-005. Reclosing relays are applied to facilitate automatic restoration of system
components following a Protection System operation.9 In certain circumstances the misoperation
of reclosing relays can impact the reliability of the Bulk-Power System.

5

Unless otherwise designated, all capitalized terms shall have the meaning set forth in the Glossary of Terms
Used in NERC Reliability Standards, available at http://www.nerc.com/files/Glossary_of_Terms.pdf
6
Reliability Standard PRC-005-2 was approved by the Commission on December 19, 2013. See Order No.
793, 145 FERC ¶ 61,253.
7
18 C.F.R. § 39.5(a) (2013).
8
The Commission specified in Order No. 672 certain general factors it would consider when assessing
whether a particular Reliability Standard is just and reasonable. See Rules Concerning Certification of the Electric
Reliability Organization; and Procedures for the Establishment, Approval, and Enforcement of Electric Reliability
Standards, Order No. 672, FERC Stats. & Regs. ¶ 31,204, at P 262, 321-37, order on reh’g, Order No. 672-A,
FERC Stats. & Regs. ¶ 31,212 (2006).
9
As reclosing relays facilitate automatic restoration, they are often referred to as “automatic reclosing
relays” or “autoreclosing relays”. The term “reclosing relay”, as used in this Petition, has the same meaning as the
terms “automatic reclosing relay” and “autoreclosing relay” as they may appear in Exhibits to this Petition.

2

In response to Order No. 758, the NERC System Analysis and Modeling Subcommittee
(“SAMS”) and System Protection and Control Subcommittee (“SPCS”) jointly performed a
technical study to determine which reclosing relays should be addressed within PRC-005 and
provide advice to the Protection System Maintenance and Testing Standard Drafting Team
(“Standard Drafting Team”) regarding appropriate maintenance intervals and activities for those
relays (“SAMS/SPCS Report”) (Exhibit D). The Standard Drafting Team developed revisions
to Reliability Standard PRC-005-2 in line with the SAMS/SPCS Report recommendations. As a
result, proposed Reliability Standard PRC-005-3 adds reclosing relays that can affect the reliable
operation of the Bulk-Power System to the applicability of Reliability Standard PRC-005 to
satisfy NERC’s commitment to address the Order No. 758 directive and provide for the
maintenance and testing of these relays.
II.

NOTICES AND COMMUNICATIONS

Notices and communications with respect to this filing may be addressed to the
following:10

Persons to be included on the Commission’s service list are identified by an asterisk. NERC respectfully
requests a waiver of Rule 203 of the Commission’s regulations, 18 C.F.R. § 385.203 (2013), to allow the inclusion
of more than two persons on the service list in this proceeding.
10

3

Charles A. Berardesco*
Senior Vice President and General Counsel
Holly A. Hawkins*
Assistant General Counsel
William H. Edwards*
Counsel
Brady A. Walker*
Associate Counsel
North American Electric Reliability
Corporation
1325 G Street, N.W., Suite 600
Washington, D.C. 20005
(202) 400-3000
(202) 644-8099 – facsimile
[email protected]
[email protected]
[email protected]
[email protected]
III.

Mark G. Lauby*
Vice President and Director of Standards
Valerie Agnew*
Director of Standards Development
North American Electric Reliability
Corporation
3353 Peachtree Road, N.E.
Suite 600, North Tower
Atlanta, GA 30326
(404) 446-2560
(404) 446-2595 – facsimile
[email protected]
[email protected]

BACKGROUND
A.

Regulatory Framework

By enacting the Energy Policy Act of 2005,11 Congress entrusted the Commission with
the duties of approving and enforcing rules to ensure the reliability of the Nation’s Bulk-Power
System, and with the duties of certifying an ERO that would be charged with developing and
enforcing mandatory Reliability Standards, subject to Commission approval. Section 215(b)(1)12
of the FPA states that all users, owners, and operators of the Bulk-Power System in the United
States will be subject to Commission-approved Reliability Standards. Section 215(d)(5)13 of the
FPA authorizes the Commission to order the ERO to submit a new or modified Reliability
Standard. Section 39.5(a)14 of the Commission’s regulations requires the ERO to file with the
Commission for its approval each Reliability Standard that the ERO proposes should become

11
12
13
14

16 U.S.C. § 824o (2012).
Id. § 824(b)(1).
Id. § 824o(d)(5).
18 C.F.R. § 39.5(a).

4

mandatory and enforceable in the United States, and each modification to a Reliability Standard
that the ERO proposes should be made effective.
The Commission has the regulatory responsibility to approve Reliability Standards that
protect the reliability of the Bulk-Power System and to ensure that such Reliability Standards are
just, reasonable, not unduly discriminatory or preferential, and in the public interest. Pursuant to
Section 215(d)(2) of the FPA15 and Section 39.5(c)16 of the Commission’s regulations, the
Commission will give due weight to the technical expertise of the ERO with respect to the
content of a Reliability Standard.
B.

NERC Reliability Standards Development Procedure

The proposed Reliability Standards were developed in an open and fair manner and in
accordance with the Commission-approved Reliability Standard development process.17 NERC
develops Reliability Standards in accordance with Section 300 (Reliability Standards
Development) of its Rules of Procedure and the NERC Standard Processes Manual.18 In its
order certifying NERC as the Commission’s Electric Reliability Organization, , the Commission
found that NERC’s proposed rules provide for reasonable notice and opportunity for public
comment, due process, openness, and a balance of interests in developing Reliability Standards19

15

16 U.S.C. § 824o(d)(2).
18 C.F.R. § 39.5(c)(1).
17
Rules Concerning Certification of the Electric Reliability Organization; and Procedures for the
Establishment, Approval, and Enforcement of Electric Reliability Standards, Order No. 672 at P 334, FERC Stats. &
Regs. ¶ 31,204, order on reh’g, Order No. 672-A, FERC Stats. & Regs. ¶ 31,212 (2006) (“Further, in considering
whether a proposed Reliability Standard meets the legal standard of review, we will entertain comments about
whether the ERO implemented its Commission-approved Reliability Standard development process for the
development of the particular proposed Reliability Standard in a proper manner, especially whether the process was
open and fair. However, we caution that we will not be sympathetic to arguments by interested parties that choose,
for whatever reason, not to participate in the ERO’s Reliability Standard development process if it is conducted in
good faith in accordance with the procedures approved by FERC.”).
18
The NERC Rules of Procedure are available at http://www.nerc.com/AboutNERC/Pages/Rules-ofProcedure.aspx. The NERC Standard Processes Manual is available at
http://www.nerc.com/comm/SC/Documents/Appendix_3A_StandardsProcessesManual.pdf.
19
116 FERC ¶ 61,062 at P 250.
16

5

and thus satisfies certain of the criteria for approving Reliability Standards.20 The development
process is open to any person or entity with a legitimate interest in the reliability of the BulkPower System. NERC considers the comments of all stakeholders, and a vote of stakeholders
and the NERC Board of Trustees is required to approve a Reliability Standard before the
Reliability Standard is submitted to the Commission for approval.
C.

History of Project 2007-17.2

In Order No. 693,21 the Commission approved Reliability Standard PRC-005-1 and
directed NERC to “develop a modification … through the Reliability Standards development
process that includes a requirement that maintenance and testing of a protection system must be
carried out within a maximum allowable interval that is appropriate to the type of the protection
system and its impact on the reliability of the Bulk-Power System.”22 In 2007, NERC initiated
Project 2007-17 Protection System Maintenance and Testing to address the Commission’s
directive.
While the Standard Drafting Team developed these revisions to PRC-005, the
Commission approved two interpretations of PRC-005-1. On April 15, 2011, NERC filed a
petition seeking Commission approval of an interpretation of Requirements R1 and R3 of
Reliability Standard PRC-004-1 (Analysis and Mitigation of Transmission and Generation
Protection System Misoperations) and Requirements R1 and R2 of Reliability Standard PRC005-1 (Transmission and Generation Protection System Maintenance and Testing). The
Commission approved NERC’s interpretation, effective as of September 26, 2011.23 On

20

Order No. 672 at PP 268, 270.
Mandatory Reliability Standards for the Bulk-Power System, Order No. 693, FERC Stats. & Regs. ¶ 31,242
(“Order No. 693”), order on reh’g, Order No. 693-A, 120 FERC ¶ 61,053 (2007).
22
Id. at P 1475.
23
N. Am. Elec. Reliability Corp., 136 FERC 61,208 (2011).
21

6

February 3, 2012, the Commission issued Order No. 758,24 approving a second interpretation of
PRC-005-1. In that Order, the Commission directed NERC to address concerns raised regarding
reclosing relays in the revisions to Reliability Standard PRC-005-1. Specifically, the
Commission directed NERC to include maintenance and testing of reclosing relays that can
affect the reliable operation of the Bulk-Power System.25
In response to Order No. 758, the Standard Drafting Team drafted a Standard
Authorization Request to modify PRC-005 to include the maintenance and testing of reclosing
relays that can affect the Reliable Operation of the Bulk-Power System. On May 10, 2012, the
NERC Standards Committee accepted the Standard Authorization Request and authorized that it
be posted for information only along with the third draft of PRC-005-2.
On July 30, 2012, NERC submitted an informational filing26 reporting to the Commission
that proposed Reliability Standard PRC-005-2—containing the revisions to Reliability Standard
PRC-005-1 outlined in Order No. 693—was in the final stages of development and that NERC
would address the Commission’s directive regarding reclosing relays in a separate petition. On
January 17, 2013, the NERC Standards Committee approved a Standard Authorization Request
to address the addition of reclosing relays through Project 2007-17.2 Protection System
Maintenance and Testing - Phase 2 (Reclosing Relays).
IV.

JUSTIFICATION FOR APPROVAL
As discussed in Exhibit C and below, proposed Reliability Standard PRC-005-3 satisfies

the Commission’s criteria in Order No. 672 and is just, reasonable, not unduly discriminatory or
Interpretation of Protection System Reliability Standard, Order No. 758, 138 FERC ¶ 61,094 (“Order No.
758”), order on reh’g, 139 FERC ¶ 61,227 (2012).
25
Id. at P 22-27.
26
NERC Jul. 30, 2012 Informational Filing in Compliance with Order No. 758, Docket No. RM10-5 (2012),
available at:
http://www.nerc.com/pa/Stand/Project%202007172%20Protection%20System%20Manintenance%20and/Final_Info
_Filing_Order_758_07-30-12_complete.pdf.
24

7

preferential, and in the public interest. The improved proposed Reliability Standard promotes
reliability by adding Automatic Reclosing to the Commission-approved Reliability Standard
PRC-005-2. The purpose of proposed PRC-005-3 is to document and implement programs for
the maintenance of all Protection Systems and Automatic Reclosing affecting the reliability of
the Bulk Electric System so that they are kept in working order.
PRC-005-3 has five Requirements that address the inclusion of Automatic Reclosing.
The revised Reliability Standard requires entities to develop an appropriate Protection System
Maintenance Program, to implement their program, and to initiate the follow-up activities
necessary to resolve maintenance issues in the event they are unable to restore Automatic
Reclosing Components to proper working order while performing maintenance. Proposed PRC005-3 adds detailed tables of minimum maintenance activities and maximum maintenance
intervals for Automatic Reclosing to the existing PRC-005-2 Reliability Standard, extending the
benefits of a strong maintenance program to these Components. The subset of Automatic
Reclosing applications included in proposed PRC-005-3 is based on the findings of the
SAMS/SPCS Report included as Exhibit D. To assist responsible entities in understanding the
addition of Automatic Reclosing to PRC-005, the Standard Drafting Team revised the
Supplementary Reference and FAQ document developed with PRC-005-2 and posted the
document concurrently with the proposed Reliability Standard during each posting. This revised
document will be posted with the proposed PRC-005-3 Reliability Standard following approval.
Proposed PRC-005-3 satisfies the Commission’s directive in Order No. 758 by including
the necessary reclosing relay applications with the potential to impact Reliable Operation of the
Bulk-Power System in the scope of Reliability Standard PRC-005. Provided below is a
summary of the recommendations from the SAMS/SPCS Report including discussion of

8

reclosing relays, an overview of the modifications to Reliability Standard PRC-005-2 necessary
to meet the Commission’s directive, and a discussion of the Implementation Plan.
A.

Reclosing Relays

Reclosing relays are utilized on transmission systems to restore transmission elements to
service following automatic circuit breaker tripping.27 There are several types of reclosing
relays, including electromechanical, solid state, and microprocessor-based, which may be applied
in a variety of scenarios.28 Most reclosing relays share three main functions: supervisory, timing,
and output.29 A relay failure is most likely to occur as part of one of these functions. Reclosing
relays are typically installed to lessen the burden on Transmission Operators of manually
restoring transmission lines.30 Relays of this type also provide improved capability in restoration
of overhead transmission lines. The degree to which such capability is improved depends on the
nature of the fault—permanent or temporary—and on Transmission Operator practices regarding
manual restoration.31
While more efficient restoration of transmission lines following temporary faults does
provide an inherent reliability benefit, certain applications of reclosing relays can result in
undesired relay operation or operation not consistent with relay design, leading to adverse
reliability impacts. Because certain applications of reclosing relays can have the potential to
impact the Bulk-Power System, it is beneficial to reliability that those relays be included under
the applicability of proposed Reliability Standard PRC-005-3.
B.

27
28
29
30
31

SAMS/SPCS Report

See SAMS/SPCS Report, Ex. D at 2.
Id. at 3.
Id. at 3-4.
Id.at 3.
Id.

9

The SAMS/SPCS Report recommended that the Standard Drafting Team modify
Reliability Standard PRC‐005-2 to: 1) explicitly address maintenance and testing of reclosing
relays applied as an integral part of a Special Protection System; and 2) include maintenance and
testing of reclosing relays at or in proximity to generating plants at which the total installed
capacity is greater than the capacity of the largest generating unit within the Balancing Authority
Area.32 For this second category, the SAMS/SPCS Report suggested to define “proximity” as
substations one bus away if the substation is within 10 miles of the plant. The SAMS/SPCS
Report also suggested including a provision to exclude reclosing relays “if the equipment owner
can demonstrate to the Transmission Planner that a close‐in three‐phase fault for twice the
normal clearing time (capturing a minimum trip‐close‐trip time delay) does not result in a total
loss of generation in the interconnection exceeding the largest unit within the Balancing
Authority Area where the autoreclosing is applied.”33 Finally, the SAMS/SPCS Report included
recommendations for minimum maintenance activities and maximum intervals based on
comparable activities and intervals included in Reliability Standard PRC‐005‐2.34
To reach these recommendations, SAMS and SPCS considered the Commission’s
concerns in Order No. 758 and summarized in the SAMS/SPCS Report that the Commission’s
concerns could be grouped into two categories: (1) situations in which reclosing relays fail to
operate when required to maintain Bulk-Power System reliability; and (2) situations in which
reclosing relays operate in a manner not consistent with design, adversely affecting reliability of
the Bulk-Power System. The SAMS/SPCS Report addresses these two categories of concern by

32
33
34

Id. at 10.
Id.
Id.

10

studying reclosing applications to improve Bulk-Power System performance and to aid in
restoration.
In assessing the first category, SAMS and SPCS noted that while successful operation of
reclosing relays will enhance reliability of the Bulk-Power System, reclosing into a permanent
power system fault may adversely impact reliability. Because the potential for permanent power
system faults exists for any application, it is not possible to depend on successful reclosing relay
operation as a sole means to guarantee reliability or satisfy the Requirements contained in
Reliability Standards. The same issues exist for single‐pole reclosing with regard to the potential
for reclosing into a permanent fault after all three poles are tripped. The exception is when
reclosing relays are included as an integral part of a Special Protection System (“SPS”). In these
applications, other functions of the SPS will operate to preserve reliability in the event that
reclosing is unsuccessful; thus, failure of any part of the SPS may adversely impact reliability of
the Bulk-Power System.
In assessing the second category, SAMS and SPCS note that reclosing relays are typically
installed to alleviate the burden on operators of manually restoring transmission lines. Reclosing
relays also provide improved availability of overhead transmission lines. The degree to which
availability is improved depends on the nature of the fault (permanent or temporary) and on
Transmission Operator practices for manually restoring lines. While faster restoration of
transmission lines following temporary faults does provide an inherent reliability benefit, it is
possible for undesired operation of the reclosing scheme, not consistent with its design, to
adversely impact Bulk-Power System reliability. Certain credible failure modes, including those
related to supervision, timing, and output, may lead to undesired reclosing relay operation which
could pose a reliability risk.

11

C.

Modifications in proposed Reliability Standard PRC-005-3

As discussed below, certain parts of Reliability Standard PRC-005-2 have been modified
in order to add the necessary reclosing relays to the PRC-005 Reliability Standard.
1.

Definitions

NERC developed one new and five revised definitions to accompany proposed PRC-0053.35 NERC proposes the following new definition to define the scope of what is included when
Automatic Reclosing is referenced within the proposed PRC-005-3 Reliability Standard:
Automatic Reclosing – Includes the following Components:

Reclosing relay

Control circuitry associated with the reclosing relay.
This definition is intended only for use within the proposed Reliability Standard and will not, at
this time, be listed in the NERC Glossary of Terms.36 The term will be included within the
posted Reliability Standard itself.37 This definition establishes that “Automatic Reclosing”
includes reclosing relays and the associated dc control circuitry and reflects the SAMS/SPCS
Report recommendation that PRC-005-3 should apply to both the reclosing relay and associated
control circuitry. The recommendation includes both Component Types since a failure in the
reclosing relay or the control circuitry may result in the same adverse reliability impact.
In addition, the previously-approved defined terms “Protection System Maintenance
Program”, “Component Type”, “Component”, and “Countable Event” were revised to add the

35

The definitions were posted in the draft PRC-005-3 Reliability Standard during the standards development
process and will be implemented concurrently with the proposed Reliability Standard.
36
NERC acknowledges the Commission’s statement in Order No. 793 that “NERC should not adopt
inconsistent definitions for the same term.” Order No. 793 at P 70. Although this term will be posted along with the
proposed Reliability Standard, NERC will not develop additional definitions of the same term approved for use in a
particular Reliability Standard. If a future standards development project seeks to broaden the applicability of a
standard-specific defined term, the defined term and where the term is posted (in the Reliability Standard or in the
NERC Glossary of Terms) would need to be revisited through the standards development process.
37
For clarity, NERC relocated the definitions specific to the PRC-005 Reliability Standard in part 6 of
Section A (Introduction) in the posted version of the proposed Reliability Standard.

12

necessary reference to “Automatic Reclosing” or the associated Table within the proposed
Reliability Standard to facilitate coverage of Automatic Reclosing Components within the
coverage of the PRC-005 Requirements. The revised definitions are as follows (changes have
been italicized for convenience):
Protection System Maintenance Program (PSMP) — An
ongoing program by which Protection System and Automatic
Reclosing Components are kept in working order and proper
operation of malfunctioning Components is restored. A
maintenance program for a specific Component includes one or
more of the following activities:






Verify — Determine that the Component is functioning
correctly.
Monitor — Observe the routine in-service operation of the
Component.
Test — Apply signals to a Component to observe functional
performance or output behavior, or to diagnose problems.
Inspect — Examine for signs of Component failure, reduced
performance or degradation.
Calibrate — Adjust the operating threshold or measurement
accuracy of a measuring element to meet the intended
performance requirement.

Component Type – Either any one of the five specific elements of
the Protection System definition or any one of the two specific
elements of the Automatic Reclosing definition.
Component – A Component is any individual discrete piece of
equipment included in a Protection System or in Automatic
Reclosing, including but not limited to a protective relay, reclosing
relay, or current sensing device. The designation of what
constitutes a control circuit Component is dependent upon how an
entity performs and tracks the testing of the control circuitry. Some
entities test their control circuits on a breaker basis whereas others
test their circuitry on a local zone of protection basis. Thus, entities
are allowed the latitude to designate their own definitions of
control circuit Components. Another example of where the entity
has some discretion on determining what constitutes a single
Component is the voltage and current sensing devices, where the
13

entity may choose either to designate a full three-phase set of such
devices or a single device as a single Component.
Countable Event – A failure of a Component requiring repair or
replacement, any condition discovered during the maintenance
activities in Tables 1-1 through 1-5, Table 3, and Tables 4-1
through 4-2 which requires corrective action or a Protection
System Misoperation attributed to hardware failure or calibration
failure. Misoperations due to product design errors, software
errors, relay settings different from specified settings, Protection
System Component or Automatic Reclosing configuration or
application errors are not included in Countable Events.
Lastly, two definitions contain capitalization changes to the previously-approved
definitions to correctly reference the defined term “Component.” The revised definitions read as
follows:
Unresolved Maintenance Issue – A deficiency identified during a
maintenance activity that causes the Component to not meet the
intended performance, cannot be corrected during the maintenance
interval, and requires follow-up corrective action.
Segment – Components of a consistent design standard, or a
particular model or type from a single manufacturer that typically
share other common elements. Consistent performance is expected
across the entire population of a Segment. A Segment must contain
at least sixty (60) individual Components.
2.

Applicability

Automatic Reclosing is addressed in PRC-005‐3 by explicitly addressing it outside the
definition of Protection System. The specific locations for applicable Automatic Reclosing are
addressed in a new subsection 4.2.6 under the listing of covered “Facilities.” The PRC‐005‐3
Supplementary Reference and FAQ document includes examples to depict which Automatic
Reclosing applications are included in the scope of the proposed PRC-005-3 Reliability
Standard. The Applicability, as detailed below, was recommended by the NERC SAMS and
14

SPCS after a lengthy review of the use of reclosing within the Bulk Electric System. SAMS and
SPCS concluded that reclosing is largely implemented throughout the Bulk Electric System as an
operating convenience, and that reclosing mal‐performance affects Bulk Electric System
reliability only when the reclosing is part of a Special Protection System, or when premature
reclosing has the potential to cause generating unit or plant instability.38
a)

Section 4.2.6.1

4.2.6.1 Automatic Reclosing applied on the terminals of Elements
connected to the BES bus located at generating plant substations
where the total installed gross generating plant capacity is greater
than the gross capacity of the largest BES generating unit within
the Balancing Authority Area.
The SAMS/SPCS Report assessed Automatic Reclosing failure modes for potential
effects to Reliable Operation of the Bulk-Power System. The report identified that premature
reclosing has the potential to cause generating unit or plant instability, and noted the impact on
Reliable Operation when the loss of generating resources exceeds the largest unit39 within the
Balancing Authority Area in which the Automatic Reclosing is applied. In this context, the
NERC Reliability Standards require consideration of loss of the largest generating unit within a
Balancing Authority Area; therefore, generation loss would not impact reliability unless the
combined capacity loss exceeds the largest unit within the Balancing Authority Area. Including
maintenance and testing of reclosing relays in PRC-005 is, therefore, appropriate for applications
of Automatic Reclosing at generating plants with capacity exceeding the largest unit within the
Balancing Authority Area.

38

See Supplementary Reference and FAQ, Ex.E at 7 (citing SAMS/SPCS Report).
See Supplementary Reference and FAQ, Ex. E at 7. In this context the capacity of the largest unit is the
value reported to the Balance Authority for generating plant capacity for planning and modeling purposes. This can
be nameplate or other values based on generating plant limitations such as boiler or turbine ratings.
39

15

The applicability includes a reference the Bulk Electric System (referred to in the
applicability section as “BES”) in order to define the generating plant bus at which Automatic
Reclosing is subject to PRC-005-3. In this context, “BES” is used to describe the high-voltage
switchyard bus on the transmission system side of the generator step-up transformer. Similarly,
“BES” is used to modify the largest generating unit with the Balancing Authority Area.
Revisions to the “Bulk Electric System” definition are unlikely to affect present classification of
generating units and buses in the context of the largest generating unit in a Balancing Authority
Area or stations with capacity that exceed the largest unit within the Balancing Authority Area.
However, PRC-005-3 will be workable regardless of how the Bulk Electric System is defined. If
an element is a Bulk Electric System Element and is located at a generating plant substation, it is
included per Section 4.2.6.1, and the Requirements for Automatic Reclosing apply.40
b)

Section 4.2.6.2

4.2.6.2 Automatic Reclosing applied on the terminals of all BES
Elements at substations one bus away from generating plants
specified in Section 4.2.6.1 when the substation is less than 10
circuit-miles from the generating plant substation.
Reclosing at transmission substations may affect the stability of generating units and
generating plants when applied in proximity to a generating plant. Therefore, the Standard
Drafting Team included applicability for Automatic Reclosing at buses in proximity to
generating plants, in addition to Bulk Electric System buses at generating plants. The criteria
that define proximity, i.e., “one bus away from generating plants specified in Section 4.2.6.1
when the substation is less than 10 circuit-miles from the generating plant substation,” originated
from the SAMS/SPCS Report. The criteria are based on the collective experience of the

40

See Section 2.4.1 in the Supplementary Reference and FAQ document, Ex. E, for additional discussion.

16

subcommittee members performing transient stability studies. Their experience reveals that for
cases in which generating units exhibit an unstable response to a bus fault at the high-side of the
generator step-up transformer, the units exhibit a stable response if the fault location is on the
order of one mile from the bus. The difference in response is based on two factors. The first is
the additional impedance between the generators and the fault. The second is that when there are
additional sources of fault current in addition to the generator, the in-feed from the other sources
makes the apparent impedance41 to the fault greater, further reducing the acceleration of the
generating units during the fault. The SAMS and SPCS members applied a safety factor in
recommending the 10-mile threshold.
c)

Section 4.2.6.3

4.2.6.3 Automatic Reclosing applied as an integral part of an SPS
specified in Section 4.2.4.
As noted in the SAMS/SPCS Report, Special Protection Systems may be applied to meet
system performance requirements in the NERC Reliability Standards or to increase the transfer
limit associated with an Interconnection Reliability Operating Limit. When reclosing is included
as an integral part of such a SPS, a failure of the reclosing function may adversely impact BulkPower System reliability.42 In such applications, it typically is essential to successfully restore
the power system to its pre-contingency state after a fault or disturbance (e.g., reclosing a
transmission line connected at a generating station after it is tripped to clear a fault). Since it is
possible that the fault or disturbance will be sustained and prevent restoration to the precontingency state, the SPS must take remedial action (e.g., initiating control system action or

41

Apparent impedance is a term that refers to the effective impedance when more than one source contributes
current through an element, resulting in an effective impedance greater than the actual impedance of the element.
42
See SAMS/SPCS Report, Ex. E at 3.

17

tripping resources to reduce power transfers) if it determines the reclosing was unsuccessful.
Unsuccessful reclosing may result from failure of the Automatic Reclosing or because of a
subsequent trip when the fault or disturbance is sustained. In these applications Reliable
Operation of the Bulk-Power System is dependent on proper operation of the SPS. This
dependence on proper operation of the SPS dictates that maintenance and testing requirements
apply to all parts of the SPS.
d)

Footnote 1 Exclusion

FN1 Automatic Reclosing addressed in Section 4.2.6.1 and 4.2.6.2
may be excluded if the equipment owner can demonstrate that a
close-in three-phase fault present for twice the normal clearing
time (capturing a minimum trip-close-trip time delay) does not
result in a total loss of gross generation in the Interconnection
exceeding the gross capacity of the largest BES generating unit
within the Balancing Authority Area where the Automatic
Reclosing is applied.
The applicability for Automatic Reclosing in PRC-005-3 is based on the SAMS and
SPCS assessment of failure modes of reclosing relays that could impact Reliable Operation of
the Bulk-Power System. During the SAMS/SPCS study, the SPCS identified the worst case
reclosing relay failure modes and SAMS assessed the reliability risk to the Bulk-Power System.
The worst case failure mode identified by SPCS is a failure that would lead to reclosing with no
time delay. SAMS identified that this failure mode presents a risk to Reliable Operation of the
Bulk-Power System when reclosing relays are used at or in proximity to generating stations,
because it could lead to generating unit instability. SAMS and SPCS concluded that
maintenance and testing of Automatic Reclosing should be required when the potential loss of
generating resources may exceed the gross capacity of the largest Bulk Electric System unit
within the Balancing Authority Area where the Automatic Reclosing is applied. Thus, the
applicability establishes a bright line to allow entities to assess which Automatic Reclosing is
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subject to requirements in PRC-005-3. Further, SAMS and SPCS recognized that failure of
Automatic Reclosing may not affect reliability of the Bulk-Power System at all locations
identified in the applicability of PRC-005-3. Determining which, if any, locations identified in
the applicability do not pose a reliability risk would require case-by-case studies of the worstcase failure mode on which the applicability is based. Rather than including a requirement in
PRC-005-3 for entities to perform such analysis, the Standard Drafting Team included Footnote
1 to allow entities the option to instead rule out certain locations at which this risk is not present.
Footnote 1 to Applicability Section 4.2.6 establishes that Automatic Reclosing addressed
in 4.2.6.1 and 4.2.6.2 may be excluded if the equipment owner can demonstrate that a close‐in
three‐phase fault present for twice the normal clearing time (capturing a minimum trip‐close‐trip
time delay) does not result in a total loss of gross generation in the Interconnection exceeding the
gross capacity of the largest Bulk Electric System unit within the Balancing Authority Area
where the Automatic Reclosing is applied. This benchmark reflects the worst-case failure mode
identified by SAMS and SPCS and, therefore, serves as a valid, technically-supported test for
ruling out certain facilities from the applicability of PRC-005-3. The test simulates a fault for
twice the normal clearing time because this is approximately the same as clearing the fault in
normal clearing time, reclosing into the fault with no time delay, and clearing the fault again in
normal clearing time.
e)

NERC Evaluation of 10-Mile Threshold

As noted above, proposed Reliability Standard PRC-005-3 requires maintenance and
testing of reclosing relays at generating stations, and at substations one bus away from a
generating station if the substation is within 10 miles of the generating station. Further, the

19

criteria are based on the collective experience of the SAMS and SPCS members and include a
safety factor in establishing the ten-mile threshold.
NERC staff has conducted an analysis to verify that the 10-mile threshold provides
adequate margin to ensure maintenance and testing of all reclosing relays where failure could
result in generating station instability. Testing was performed at the high-voltage switchyard for
50 generating stations. A sample of generating stations was used with high-side voltage ranging
from 115 kV to 765 kV. The sample included a wide range of generating unit types,
transmission line lengths, and switchyard configurations, and is therefore representative of
generating stations across North America. Three-phase faults were simulated on each line43
exiting each generating station. Faults were simulated for a duration that conservatively
represents two times the normal clearing time for a three-phase fault. This test is based on a
recommendation in the SAMS-SPCS Report to apply a close-in three-phase fault for twice the
normal clearing time (capturing a minimum trip-close-trip time delay). This test approximates
the response if a transmission line circuit breaker is reclosed into a fault without any time delay
due to a reclosing relay failure. The fault durations used in the study are 8 cycles at voltage
greater than 300 kV, 10 cycles for clearing times for voltage between 200 kV and 300 kV, and
12 cycles for voltage below 200 kV. Close-in faults were applied on each line on the line side of
the circuit breaker(s). In cases where the generating unit response was unstable, the fault was
reapplied at one-mile increments away from the bus until the generating unit response was
stable. Testing was performed on a total of 145 transmission lines at 50 generating stations. The
generating unit response was stable for 110 of the close-in faults. For the remaining 35 lines, the

43

When two or more parallel lines exit a generating station and terminate at the same remote station, a fault
was applied on only one line since the response would be essentially the same faults on each line.

20

generating response was stable for faults one mile from the generating station in 22 cases and
was stable for faults greater than five miles from the generating station in 10 cases.
The three remaining cases involve two generating stations. At one station, the two
transmission lines exiting the station are approximately 120 miles long. On one line, the
generating units were stable for a fault 11 miles from the generating station and on the other line
the generating units were unstable for faults anywhere on the line. At this generating station the
predominant factor in the generating unit instability is the post-fault system impedance with the
generating units remaining connected to one 120-mile line. The analysis was repeated at each
remote bus at the remote terminal of the two 120-mile lines. The generating units were stable for
close-in three phase faults on each line terminating at these remote buses. Since these remote
buses are more than 10 miles from the generating station, PRC-005-3 would not be applicable to
the reclosing relays and the analysis confirms there is not a reliability need to include these
relays.
At the second generating station, one of the lines exiting the station is approximately two
miles in length. The generating units were unstable for faults anywhere on this line. Proposed
Reliability Standard PRC-005-3 would be applicable to reclosing relays at the remote bus
because it is less than 10 miles from the generating station. In this case the generating units
remain stable for close-in faults on each of the lines terminating at the remote bus, confirming
that the criterion is conservative.
3.

Changes to Requirements in Reliability Standard PRC-005-2

The proposed Reliability Standard consists of five Requirements. The Requirements and
the associated Measures have been modified, as necessary, to add in the coverage of Automatic
Reclosing to the Requirement language.

21

Requirement R1 now requires that Transmission Owners, Generator Owners, and
Distribution Providers establish a Protection System Maintenance Program both for Protection
Systems and for Automatic Reclosing relays as defined in the proposed Reliability Standard,
and, as in Reliability Standard PRC-005-2, includes guidelines for the development of such a
program.
Requirement R3 now requires Transmission Owners, Generator Owners, and Distribution
Providers that utilize time-based maintenance programs to maintain Protection Systems and
certain automatic reclosing relays as defined within the proposed Reliability Standard.
Requirement R4 now requires Transmission Owners, Generator Owners, and Distribution
Providers that utilize performance-based maintenance programs to implement and follow a
PSMP for Protection Systems and for Automatic Reclosing relays as defined within the proposed
Reliability Standard.
Revisions to Requirements R2 and R5 were not necessary as each will apply in the same
fashion in proposed Reliability Standard PRC-005-3 as approved by the Commission in
Reliability Standard PRC-005-2.
D.

Implementation Plan

The Implementation Plan for proposed Reliability Standard PRC-005-3 addresses both
Protection Systems and Automatic Reclosing. PRC-005-2 has recently been approved by the
Commission and has a twelve-year phased-in implementation period. The compliance dates for
the various Requirements with respect to maintenance of Protection System Components in
PRC-005-2 key off of the date of approval by the applicable regulatory authority. To account for
this timing, and in order not to lose time on maintenance activities completed prior to the
approval of PRC-005-3, the Standard Drafting Team has carried forward the language in the

22

implementation plan for PRC-005-2 and modified it to add compliance dates for the
Requirements with respect to Automatic Reclosing Components. The Standard Drafting Team
also modified the language for the compliance dates for Requirements with respect to Protection
System Components to explicitly reference that the compliance timing for these Components
counts forward from the applicable regulatory authority approval date for PRC-005-2. As a
result, the Implementation Plan for PRC-005-3 captures the necessary implementation
information for PRC-005-2. Under the Implementation Plan for PRC-005-3, entities will now, as
an initial matter, indicate whether their Component is being maintained under one of the legacy
Reliability Standards (PRC-005-1b, PRC-008-0, PRC-011-0, and PRC-017-0) or whether the
Component is being maintained pursuant to PRC-005-3. Because PRC-005-3 has carried the
Requirements from PRC-005-2 forward, including language regarding implementation timing,
there is no need for an entity to cite to the version 2 Reliability Standard during the phased-in
implementation period once the proposed Reliability Standard is approved.44 Additional aspects
of the Implementation Plan are addressed below.
1.

Retirement of Legacy Reliability Standards

The Implementation Plan continues to reflect that the retirement of the legacy Reliability
Standards will continue to key off of the applicable regulatory approval date of PRC-005-2.
Because Automatic Reclosing is a new Component covered by the PRC-005 Reliability
Standard, the retirement of the legacy Reliability Standards does not need to correspond with the
enforcement date of proposed PRC-005-3. Proposed PRC-005-3 will retire Reliability Standard
PRC-005-2 in the United States “at midnight of the day immediately prior to the first day of the

44

The same approach will be used with respect to the addition of sudden pressure relays. This will allow for
the full retirement of PRC-005-3 and its implementation plan leaving only one version of a new PRC-005 standard
as the enforceable Reliability Standard rather than needing to reference versions 2 through 4 for the next twelve
years.

23

first calendar quarter, twelve (12) calendar months following applicable regulatory approval of
PRC-005-3.”
2.

Compliance Timeframes for Each Requirement

The Implementation Plan includes identical timeframes for entities to become compliant
with the Requirements in PRC-005-3 as exist in the implementation plan for PRC-005-2. The
only difference is the date from which entities will count forward to determine the date the entity
must be compliant for a particular Component Type. Entities will continue to calculate
compliance dates for Requirements in connection with any Protection System Components by
counting forward from the applicable regulatory approval date of PRC-005-2. Entities will
continue to calculate compliance dates for Requirements in connection with any Automatic
Reclosing Components by counting forward from the applicable regulatory approval date of
PRC-005-3.
3.

Newly Identified Automatic Reclosing Components

The Implementation Plan also includes implementation timeframes for newly identified
Automatic Reclosing Components due to generation changes in the Balancing Authority Area.
Additional applicable Automatic Reclosing Components may be identified because of the
addition or retirement of generating units; or increases of gross generation capacity of individual
generating units or plants within the Balancing Authority Area. The Implementation Plan
provides that “ [i]n such cases, the responsible entities must complete the maintenance activities,
described in Table 4, for the newly identified Automatic Reclosing Components prior to the end
of the third calendar year following the identification of those Components unless documented
prior maintenance fulfilling the requirements of Table 4 is available.”

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E.

Evidence Retention Periods

In order to establish effective maintenance procedures to ensure Reliable Operation of
the Bulk-Power System, the Standard Drafting Team established certain evidence retention
periods, which were approved by the Commission with Reliability Standard PRC-005-2. Those
same evidence retention periods are maintained in proposed Reliability Standard PRC-005-3.
These periods will now apply to evidence retained for compliance with the Requirements in
connection with Automatic Reclosing. Proposed PRC-005-3 continues to require entities to
maintain documentation for the longer of: (1) the two most recent performances of each distinct
maintenance activity for the Protection System or Automatic Reclosing Component; (2) all
performances of each distinct maintenance activity for the Protection System or Automatic
Reclosing Component since the previous scheduled audit date. The Standard Drafting Team
explains that this requirement assures that documentation is available to show that the time
between maintenance cycles correctly meets the maintenance interval limits.45 Maintaining
elements according to these intervals is a critical aspect of properly maintaining a covered
Component. Because some maintenance intervals in proposed PRC-005-3 (and the predecessor
Reliability Standard PRC-005-2) are up to twelve years, it is possible that an entity may need to
retain records for up to twenty-four years.
The evidence retention periods in proposed Reliability Standard PRC-005-346 continue to
be reasonable for this type of activity. The type of evidence entities will retain to demonstrate
that maintenance was last completed within a given interval are the usual and customary
documents maintained by these entities today to document maintenance internally of various

45

See Supplementary and FAQ, Ex. E at 39.
The evidence retention periods are outlined in the Compliance section of proposed Reliability Standard
PRC-005-3, attached hereto as Exhibit A. The written description of the evidence retention periods corresponds to
the Maintenance Interval and Maintenance Activities section of Table 1, also found in Exhibit A.
46

25

components. While the time intervals may seem longer than an entity may reasonably retain
such records, the lengthy periods are necessary to establish maintenance has occurred according
to the mandated intervals. Retaining records for the two most recent performances of each
distinct maintenance activity, where the interval is twelve years, is how the twenty-four year
retention period arises. Shortening the time period for retention would require that the
maintenance intervals be reduced as well, which would significantly increase capital
maintenance costs since entities would need to maintain Components under tighter time
constraints.
The Measures in the proposed Reliability Standard provide examples of acceptable types
of evidence for each Requirement, but the Measures do not mandate specific records be kept.
Therefore, entities will have the flexibility to determine the level of documentation needed to
verify this limited element of the proposed Reliability Standard. Generally, entities will likely
only maintain summaries of their maintenance activities pertaining to the prior period in order to
establish that the proper intervals were met. Therefore, the burden will be minimal compared to
the increased capital costs that would result from shortening the intervals to create a shorter
maximum retention time.
Recognizing that the period is long, NERC has requested that the Standard Drafting
Team consider possible alternatives or refinements to the evidence retention periods in the PRC005 Reliability Standard for all covered Component Types as part of NERC Project 2007-17.3 –
Protection System Maintenance and Testing (Sudden Pressure Relays).
F.

Enforceability of proposed Reliability Standard PRC-005-3

The proposed Reliability Standard includes Violation Risk Factors (“VRFs”) and
Violation Severity Levels (“VSLs”). The VRFs and VSLs for the proposed Reliability Standard

26

comport with NERC and Commission guidelines related to their assignment. For a detailed
review of the VRFs, the VSLs, and the analysis of how the VRFs and VSLs were determined
using these guidelines, please see Exhibit G.
Because the Requirements contained in proposed Reliability Standard PRC-005-3 track
with those contained in the already approved Reliability Standard PRC-005-2, the Standard
Drafting Team determined that no revisions were necessary to the VRFs for the proposed
Reliability Standard. NERC, therefore, requests that the Commission approve the VRFs as
applied to the Automatic Reclosing Components now included in the proposed Reliability
Standard.
The VSLs in PRC-005-2 have been revised accordingly to add the additional Component
into the levels of severity. The changes are consistent with the approach taken for the VSLs in
Reliability Standard PRC-005-2. The VSLs provide guidance on the way that NERC will
enforce the Requirements of the proposed Reliability Standard for each of the Component Types.
The proposed Reliability Standard also include Measures that support each Requirement
to help ensure that the Requirements will be enforced in a clear, consistent, and non-preferential
manner and without prejudice to any party.
V.

CONCLUSION
For the reasons set forth above, NERC respectfully requests that the Commission:
•
•

approve the proposed Reliability Standard and other associated elements included in Exhibit
A;
the new and revised definitions, as noted herein;

•

the VRFs and VSLs (as explained in Exhibit E);

•

approve the Implementation Plan included in Exhibit B; and

•

approve the retirement of Reliability Standard PRC-005-2, as proposed in the
Implementation Plan.

27

Respectfully submitted,
/s/ William H. Edwards
Charles A. Berardesco
Senior Vice President and General Counsel
Holly A. Hawkins
Assistant General Counsel
William H. Edwards
Counsel
Brady A. Walker
Associate Counsel
North American Electric Reliability
Corporation
1325 G Street, N.W., Suite 600
Washington, D.C. 20005
(202) 400-3000
(202) 644-8099 – facsimile
[email protected]
[email protected]
[email protected]
[email protected]
Counsel for the North American Electric
Reliability Corporation

Date: February 14, 2014

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